Chain saw



FIG. 1 is a right side elevational view thereof;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a plan view thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a rear elevational view thereof; and,

FIG. 6 is a bottom elevational view thereof.

The broken line showing of the bar is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a chain saw, as shown and described. 